Combining two IAS Servers to make one.

I know if you are making a new server you can do a netsh aaaa show config >c:ias.txt then do a netsh exec c:\ias.txt to copy over to a new server. Lets say I already did this. Now I have a colleague who wants to add his information over to my server. How can I do this without loosing my information that is already present. If I take my colleagues information netsh exec bobias.txt then it will copy all his information and all of my information that I already have saved in IAS will be gone. Is there a way to accomplish this.
Thanks
Scott